"Oh Well" is a song first recorded by Fleetwood Mac in 1969, composed by vocalist and lead guitarist Peter Green. It first appeared as a Fleetwood Mac single in various countries in 1969 and subsequently appeared on revised versions of that year's Then Play On album and the Greatest Hits album in 1971.

"Oh Well, Part 1" has been viewed by some critics as one of the early crossovers between blues rock and heavy metal, along with songs by others such as Led Zeppelin. Indeed, John Paul Jones drew inspiration from "Oh Well, Part 1" when composing the riff to "Black Dog". John Brackett, a former professor from the University of Utah, notes that both songs employ "call and response vocals and a syncopated ascending chromatic motif that finishes with a long sustained note". Although recorded on a multitrack recorder, the song is not available in true stereo.